Not able to change synchronization interval

On my S6, I’m not able to change the synchronization interval. I simply do not see any settings. The only thing I have is “Einstellungen zur Fehlersuche” (Settings for error diagnostics) which shows me two checkboxes for http-compression and for log the network traffic. If I go to my owncloud account, I can switch on/off the sync, nothing else.
I guess this is a restriction on my phone, but it is rooted. May somebody can tell me how I can give davdroid the necessary rights.
Thanks it advance.